We appreciate Dharmarajan and Krumholz's thought-provoking comments about our article and its implications for patients and hospitals. In response, we would like to emphasize a few points. For several years, investigators have criticized the 30-day window used to determine hospital readmissions penalties (1), suggesting that shorter windows reflect “more preventable” readmissions (2). Our approach was different. We have learned that, for many diseases, the causes of poor outcomes differ over time and that treatments correspondingly need to change over time. For example, early treatment of stroke differs profoundly from later treatment. Early causes of death from myocardial infarction differ from later causes. Why should readmissions be any different? Could the pathophysiology of early and late readmissions differ? Thus, the overarching goal of our study was to explore whether predictors of readmission shift over the 30 days after hospital discharge. Despite the limitations acknowledged in our article and in the accompanying editorial, we believe that our data convincingly make this case.